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Tiffany is a member of the chess club. She won 75% of her first 32 games this year. How many games in a row does she need to win to have a winning percentage of exactly 80%?

User Torleif
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Final answer:

To find out how many games Tiffany needs to win in a row to have a winning percentage of exactly 80%, we set up an equation and solve for the number of wins required. Using the equation (24 + x) / (32 + x) = 80%, we find that Tiffany needs to win 8 more games in a row.

Step-by-step explanation:

To find out how many games in a row Tiffany needs to win to have a winning percentage of exactly 80%, we need to understand the concept of winning percentage.

Winning percentage is calculated by dividing the number of wins by the total number of games played and then multiplying by 100%. We can set up an equation to solve for the number of wins required.

Let x be the number of games Tiffany needs to win. We know that she won 75% of her first 32 games, so the number of wins is 0.75 * 32 = 24.

The total number of games played after Tiffany wins x games in a row will then be 32 + x. Using this information, we can set up the following equation:

(24 + x) / (32 + x) = 80%

To solve for x, we can cross multiply:

0.8 * (32 + x) = 24 + x

25.6 + 0.8x = 24 + x

0.8x - x = 24 - 25.6

-0.2x = -1.6

x = -1.6 / -0.2

x = 8

Therefore, Tiffany needs to win 8 more games in a row to have a winning percentage of exactly 80%.

User Larry Eitel
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